OK - I'll give it a go.
FHA - Upfront Mortgage Insurance is 1.75% of the base loan amount, this can be financed. There is a monthly MI payment at a 0.55% factor. LTV is a maximum of 96.5%, so your loan amount is $143,785. Your upfront MI would be $2,516.24. If you finance the Upfront MI, your final loan amount would be $146,301. Borrower is required to have 3.5% of his own funds in to the transaction - at $149,000 purchase price that's $5,215 you are required to have in to the transaction (that's over and above any closing fees and pre paid items that you may have to pay).
USDA - Loan guarantee fee is 2% of the final loan amount, which can be financed. That is a one time fee, and you are not required to pay a monthly MI. Loan can be financed for 100% of the purchase price, up to 102% if you finance the guarantee fee. You don't have to have a minimum investment in to the transaction. So the way we figure it for your loan guarantee fee is $149,000 X 102% = $151,980 for your loan amount, final guarantee fee is 2% of that, so it would be $3,039.60.
So on an FHA you will have a lower loan amount, lower upfront fee, and 3.6% equity in the home to start. RD no equity in the home, and a higher loan amount. FHA interest rates are often lower than on an RD loan, but you have that monthly MI that you have to pay.
I would have your loan officer do a comparison as to what your payments would be, and what the final total costs would be between the two. They both have their pros and cons, and you will need to decide based on information you're given which one would work out best for your situation.
Hope that's clear enough.